Currenty the latest thing run during a suspend to idle attempt is
the LPS0 `prepare_late` callback and the earliest thing is the
`resume_early` callback.
There is a desire for the `amd-pmc` driver to suspend later in the
suspend process (ideally the very last thing), so create a callback
that it or any other driver can hook into to do this.
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
changes from v3->v4:
* drop use of mutex, use lock_system_sleep instead
* don't pass argument of context, driver will maintain this internally
* don't allow failing prepare stage
* don't allow unregistering if sleep_no_lps0 is set
changes from v2->v3:
* Check that callbacks exist before calling
changes from v1->v2:
* Change register/unregister arguments to be struct
drivers/acpi/x86/s2idle.c | 40 +++++++++++++++++++++++++++++++++++++++
include/linux/acpi.h | 10 +++++++++-
2 files changed, 49 insertions(+), 1 deletion(-)
diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index abc06e7f89d8..8cd9a1016368 100644
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -86,6 +86,8 @@ struct lpi_device_constraint_amd {
int min_dstate;
};
+static LIST_HEAD(lps0_s2idle_devops_head);
+
static struct lpi_constraints *lpi_constraints_table;
static int lpi_constraints_table_size;
static int rev_id;
@@ -444,6 +446,8 @@ static struct acpi_scan_handler lps0_handler = {
int acpi_s2idle_prepare_late(void)
{
+ struct acpi_s2idle_dev_ops *handler;
+
if (!lps0_device_handle || sleep_no_lps0)
return 0;
@@ -474,14 +478,26 @@ int acpi_s2idle_prepare_late(void)
acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_ENTRY,
lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
}
+
+ list_for_each_entry(handler, &lps0_s2idle_devops_head, list_node) {
+ if (handler)
+ handler->prepare();
+ }
+
return 0;
}
void acpi_s2idle_restore_early(void)
{
+ struct acpi_s2idle_dev_ops *handler;
+
if (!lps0_device_handle || sleep_no_lps0)
return;
+ list_for_each_entry(handler, &lps0_s2idle_devops_head, list_node)
+ if (handler->restore)
+ handler->restore();
+
/* Modern standby exit */
if (lps0_dsm_func_mask_microsoft > 0)
acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_EXIT,
@@ -524,4 +540,28 @@ void acpi_s2idle_setup(void)
s2idle_set_ops(&acpi_s2idle_ops_lps0);
}
+int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg)
+{
+ if (!lps0_device_handle || sleep_no_lps0)
+ return -ENODEV;
+
+ lock_system_sleep();
+ list_add(&arg->list_node, &lps0_s2idle_devops_head);
+ unlock_system_sleep();
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_register_lps0_dev);
+
+void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg)
+{
+ if (!lps0_device_handle || sleep_no_lps0)
+ return;
+
+ lock_system_sleep();
+ list_del(&arg->list_node);
+ unlock_system_sleep();
+}
+EXPORT_SYMBOL_GPL(acpi_unregister_lps0_dev);
+
#endif /* CONFIG_SUSPEND */
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 6274758648e3..47c16cdc8e0e 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1023,7 +1023,15 @@ void acpi_os_set_prepare_extended_sleep(int (*func)(u8 sleep_state,
acpi_status acpi_os_prepare_extended_sleep(u8 sleep_state,
u32 val_a, u32 val_b);
-
+#ifdef CONFIG_X86
+struct acpi_s2idle_dev_ops {
+ struct list_head list_node;
+ void (*prepare)(void);
+ void (*restore)(void);
+};
+int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg);
+void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg);
+#endif /* CONFIG_X86 */
#ifndef CONFIG_IA64
void arch_reserve_mem_area(acpi_physical_address addr, size_t size);
#else
--
2.34.1
